Awl-shifting and stitch-regulating mechanism for leather-stitching machines



June 16,, 1925. v 1,541,800

1.. J. DU mus ET AL AWL SHIFTI NG AND STITCH REGULATING MECHANISM FORLEATHER STITCHING MACHINES 2' SheetS-Sheet 1 Filed Oct. 5, 1923 June 16,1925.

L. J. DU MAIS ET AL AWL SHIFTING AND STITCH REGULATING MECHANISM FORLEATHER STITCHING MACHINES 2 Sheets-Sheet 2 Filed Oct. 5, 1925 3. 3 5 z3 m w ww a w n W 4. was w l 1 w U1. a a 5 M u. m i fl 2 a .fimflfimiggHim Patented June 16, 1925.

UNITED STATES PATENT OFFICE.

LEO J. DU MAIS AND FLOYD E. MINER, OF CHICAGO, ILLINOIS, ASSIGNORS T0CHICAGO SHOE MACHINERY COMPANY, OF CHICAGO, ILLINOIS, A CORPORATION OFILLINOIS.

AWL-SHIFTING AND surrrcn-nnecnnrrns MECHANISM non. LEATHER-STITCHINGMACHINES.

Application filed October 3, 1923. Serial No. 666,237.

To all whom it may concern:

Be it known that we, Leo J. DU MAIS and FLOYD E. MINER, citizens of theUnited States, and residents of the city of Chicago, in the county ofCook and State of Illinois, have jointly invented certain new and usefulImprovements in Awl-Shifting and Stitch-Regulating Mechanism forLeather- Stitching Machines, of which the following is a specification.

This invention relates, generally, to that type of sewing machinesemployed in the manufacture and repairing of leather goods, particularlyboots and shoes, wherein a work-support or throat-plate is horizontallymounted at the front end of the machine, on which the work is supported,pierced and fed along by an oscillatory and slidably mounted awl,operating from the lower side of the work for oo-action with anoscillatory notched or hooked needle operating from the upper side ofthe work, and has especial relation to mechanism for shifting the awl ofsuch a machine laterally, and to means for adjusting movements v of suchmechanism.

The principal object of the invention is to provide a mechanism of theabove mentioned character which shall be extremely simple inconstruction and eflicient in operation, with its parts so constructed,ar-

ranged and co-operating with one another that the work will bepositively fed by the awl along the work support, and for the samedistance at each operation or cycle of the machine, thereby affordinguniformity in the distances between the openings formed in the work bythe awl for the reception of the needle, and consequently,

regulation of and uniformity in the length of the stitches.

A further object of the invention is the provision of means whereby thelateral movement of the awl can be quickly and with great accuracyadjusted so as to insure the proper alignment of the same relative tothe needle whereby the latter will,

with certainty, enter the hole in the work made by the awl.

The invention consists ,in certain pecuharities of the construction,novel arrangement and combination of the various parts thereof as willbe hereinafter more fully set forth and specifically claimed.

In the accompanying drawings, which serve to illustrate an embodiment ofthe in-- vention, and in which like characters of reference designatesimilar parts throughout the different views,

Figure l is a View partly in section and partly in elevation of afragment of a leather stitching machine of the general type abovereferred to embodying our improvements, the sectional part of said viewbeing taken on line 1-1 of Fig. 2, looking in the direction indicated bythe arrows.

Fig. 2 is a vertical sectional view taken on line 22 of Fig. 1 asindicated by the arrows.

Fig. 8 is a plan sectional view taken on line 38 of Fig. 2.

Fig. 4 is a detached perspective view of the upper portion of a cam-barof the mechanism employed for shifting the awl and needle carrying shaftlongitudinally or laterally with respect to the machine, and

Fig. 5 is a detached perspective view of a portion of said shaft.

Referring to the drawings, the reference numerals 10 and 11 designate apair of upright standards forming a part of the frame ofthe machine andlocated at the front part of the base thereof side by side and in spacedrelation to one another. The standard 10 is provided at its upperportion with a forwardly and horizontally disposed extension 12 which isformed on its side adjacent the standard 11with a vertically dis posedrectangular shaped recess 13 which extends through the upper end of saidextension, as is clearl 1 shown in Fig. 2 of the drawings, in which viewit will be observed that this recess has its lower wall 14: downwardlyinclined towards the standard 11 or towards the surface of the extension12 adjacent said standard. Communicating with the lower portion of therecess 13 is a rectangular guide-way 15 for the reception and operationof a bar 16 of similar shape in cross-section to the guide-way 15. Thisbar 16 has its upper portion laterally and outwardly deflected at anangle of about 30 degrees, to said bar, which deflected portion providesa cam 17 for co-operation with the awl carrying shaft of the machine aswill be presently explained.

The recess 13 and guide-way 15 extension 12 are covered by a plate 18secured to the extension 12 by means of screws 19, see Fig. 1 of thedrawings. Mounted on the front portion of the extension 12 of thestandard 10 and the front upper portion of the standard 11 is ahorizontally and transversely disposed work-support or throat-plate 20which is provided with an elongated opening 21 for the reception andoperation of the needle and awl of the machine, the said opening beingdisposed par allel to the driving shaft 22, which shaft is transverselyjourna'led on the frame of the machine rearwardly of the standards 16and 11 in the usual or any well known way.

Located in suitable openings in the upper portions of the standard 11and the forward extension 12 of the standard 10, is the awl carryingshaft 23 which is adapted for slidable movement laterally with respectto its supports. This shaft intersects the recess 13 and is provided inits portion within said recess with a lateral y and vertically inclinedchannel 24 of a size and shape to snugly embrace three sides of theinclined cam 17 or portion of the bar 16, which bar has its portionbelow the extension 12 screwthreaded as is clearly shown in Figs. 1 and2 of the drawings. The rear surface of the cam or portion 17 of said barrests against the face of the rear wallof the recess 13 by whicharrangement it will be understood that the cam or portion 17 will becompletely encompassed by the channel 24 of tl e slidable shaft 23 andthe aforesaid wall of the recess 13 in such a ay that in its verticalmovements the bar and its cam or portion 17 will cause lateral movementof said shaft.

Fulcrumed near its front end on a shaft 25 horizontally journaled on thestandards 10 and 11 at a suitable distance below the work-support 20 andextension 12 is a lever 26 which carries on its rear end a roller 27 forco-action with a cam groove 28 in one. of the faces of a disk 29 mountedon the drive shaft of the machine to rotate with said shaft. The frontend of the lever 26 is forked or provided with a pair of laterallyspaced prongs 30 each of which has its upper and lower surfaces roundedas is clearly shown in Fig. 1 of the drawings. Mounted on thescrew-threaded portion of in the the bar 16 in threaded engagementtherewith, is an adjusting nut which is designated as a whole by thereference numeral 31 and comprises a cylindrical portion havingtherethrough a vertical and screw-threaded aperture for engagement wit-hthe screwthreaded portion of the cam bar. T he cyl indrical part 32 ofthe adjusting nut 31 is provided at its upper portion with an annularflange and at its lower portion with another annular flange 34 which iseina ged at its lower part and milled as at for the purpose of providingconvenient means for turning said nut in order to adjust the bar 16 withrespect to the front end of the lever 26 which in the operation of themachine reciprocates said bar as will be presently explained.

By reference to Figs. 1 and 2 it will be seen that the rounded portionsof the prongs 30 of the lever 26 rest against the adjacent surfaces ofthe flanges 33 and and on opposite sides of the cylindrical part of theadjusting nut so that said prongs may have rocking contact with saidflanges. Mounted on the lower portion of the screwthreaded part of thebar 16 is a lock nut 36 employed for maintaining the nut 31 in itsadjusted position.

Referring again to the awl and needle carrying shaft 23 it will beobserved ly reference to Figs. 2 and 3 that this shaft is provided at asuitable distance from the inner surface of the standard 11, in whichone end of the shaft is mounted, with a fixed annular flange 37 and hassurrounding its bearing portion a sleeve 38 provided on its inner endwith an annular flange 39 which is spaced from the flange 37 and isfixed on the shaft 23 by means of a pin 40 extended through suitableopenings in the sleeve and said shaft. Mounted on the shaft be tween theflanges 37 and 39 is a carrier 41 for the awl 42, which awl may besecured to the carrier in any well known way but usually by means ofclamping plate 13 and a screw 44 extended through a suitable openin insaid plate and seated in a snitable opening in the carrier.

The rear portion of the carrier 41 terminates in a segment or segmentalrack having teeth 46 to mesh with teeth 41' on a se mental rack 48having operative connection 48 with a suitable cam on the driving shai"t 22 of the machine for imparting oscillatory movement to the carrier 41and its awl.

Surrounding the shaft 23 and screwed at one of its ends into an openingin the plate 18 which covers the recess 13 in the eaten 52 of themachine, which needle may be secured to its carrier in any well knownway but usually by means of a clamping plate 53 and a screw 54 extendedthrough suitable openings in said plate and carrier and held in positionby means of a nut 55' on the opposite side of the carrier from that ofthe head of said screw. The rear portion of the carrier 01 terminates ina segmental rack 56 having teeth 57 to mesh with teeth 58 on a segmentalrack 59 having operative connection 59 with a suitable cam on thedriving shaft 22 of the machine for imparting oscillatory movement tothe carrier 51 and its needle.

Inasmuch as the mechanisms for oscillating the awl carrier so as tocause the awl to pierce the work and for oscillating the needle carrierso as to cause the needle to enter the opening formed by the awl, iswell known in the art, and as different mechanisms for performing saidfunctions may be employed, we have not herein shown fully or completelysuch mechanism but enough thereof for an understanding of theoscillatory operation of the needle and awl carriers.

From the foregoing and by reference to the drawings, it will be readilyunderstood and clearly seen that in the sewing operation of the machinethe rod 16 will, through the instrumentality of the cam actuated lever26, be vertically reciprocated and that in the movements of the cam orportion 17 of the bar 16, through the channel 24 of the shaft 23, thelatter will be slid back and forth in its bearings in such a way thateach hole pierced by the awl 42 will be positioned by the awl before thelatter leaves the work at a point to be entered with certainty by theneedle. It is further evident that when the parts, that is, the bar 16,cam

17, nut or block 31, and shaft 23, as well as the lever 26, arepositioned as shown in the drawings and particularly in Figs. 1 and 2thereof, the upper end of the cam 17 will rest against the side wall ofthe recess 13 with its heel or lower corner located in the extreme upperportion of the recess 2% of the shaft 28. When in these positions themechanism is set for making the longest stitches of which it is capable.Now, by turning the nut 31 in the proper direction, on thescrew-threaded portion of the shaft 16, the flanges 33 and 3 1 of saidnut engaging the forks 3O therebetween of the lever 26 being held in afixed position while its adjustment is being done, will cause the cam 17to be moved downwardly through the recess 24: of the shaft 23 thusforcing the shaft to the left of Fig. 2, thereby shortening the movementof the shaft 23 and consequently the stitches.

Having thus fully described our invenawl to cause it to penetrate thework, and

means for actuating said bar to cause the awl to feed the worklaterally.

2. The combination with a shaft mounted for reciprocation horizontallyand trans versely on a sewing machine rearwardly of the work-supportthereof, of an awl mounted for oscillation on said shaft, a bar mountedfor vertical movement below said shaft and having at its upper portionan inclined cam co-operating with said shaft for shifting the same backand forth, means for oscillating the awl to cause it to penetrate thework, and means for actuating said bar to cause the awl to feed the worklaterally.

3. Thecombination with a shaft mounted for reciprocation horizontallyand transversely on a sewing machine rearwardly of the work-supportthereof and provided with a vertically inclined channel, of an awlmounted for oscillation on said shaft, a bar mounted below said shaftfor vertical move ment and having at its upper portion an inclined camlocated in and slidably cooperating with said channel in said shaft,means for oscillating the awl to cause it to penetrate the work, andmeans for actuating said bar, said means including a cam-operated leverand means on said bar for adjustably connecting the bar to the lever.

i. The combination with a shaft mounted for reciprocation horizontallyand trans versely on a sewing machine and provided with a verticallyinclined channel, of a bar mounted below said shaft for verticalmovement and having at its upper portion a vertically inclined camlocated in and slidably co-operating with said channel in said shaft,said bar having its lower portion screw-threaded, an awl carrier mountedfor oscillation on said shaft but for reciprocation therewith, asegmental rack on the rear portion of said carrier, a cam-operatedsegmental rack meshing with the first named rack for impartingoscillatory movement to the awl carrier for causing the awl to penetratethe work, an adjusting nut mounted on the screw-threaded portion of saidbar and having a pair of flanges spaced one above the other, and acam-operated lever provided with a pair of prongs to stride the body ofsaid nut and to rockingly engage its flanges.

5. The combination with a shaft mounted nel in said shaft, means foroscillating the awl to cause it to penetrate the Work, means 10 foractuating said bar vertically to cause the awl to feed the worklaterally, and means co-operating with said actuating means forvertically adjusting said bar.

LEO J. DU MAIS. FLOYD E. MINER.

